Spatiotemporal drought assessment using vegetation health index and standardized precipitation index over Sudano-Sahelian region of Nigeria. Issue 4 (2nd October 2021)

• Record Type: Journal Article
• Authors: Ekundayo, O. Y.; Okogbue, E. C.; Akinluyi, F.O; Kalumba, A.M; Orimoloye, I.R
• Is Part Of: African geographical review. Volume 40:Issue 4(2021)
• Page Start: 412
• Page End: 424
• Publication Date: 2021-10-02
• Subjects: Nigeria Sudano-Sahelian region -- drought -- severity -- Standardized Precipitation Index (SPI) -- Vegetation Health Index (VHI); Africa -- Geography -- Periodicals; Africa -- Description and travel -- Periodicals; 916.005
• DOI: 10.1080/19376812.2020.1841658
• Languages: English
• ISSNs: 1937-6812

Abstract

ABSTRACT: Drought events were assessed using remote sensing index (Vegetation Health Index, VHI) and meteorological index (12-month Standardized Precipitation Index, SPI-12) over the Sudano-Sahelian Region of Nigeria (SSRN) between 2000 and 2010. Rainfall data of the SSRN were acquired from nine stations of the Nigerian Meteorological Agency (NIMET). Monthly Vegetation Index (MOD13A3) and 8-day Land Surface Temperature (MOD11A2) of the Moderate-Resolution Imaging Spectroradiometer (MODIS) were retrieved from the NASA's Land Data Product and Services Center (LPDAAC) website. The result from VHI evaluation revealed that about 121.926 km 2 and 36.063 km 2 of the region experienced extreme drought in the years 2003 and 2010, respectively, while SPI-12 detected no extreme drought condition during the same period. Both indices detected severe, moderate, and mild droughts (mild drought dominated the SPI-12 results) occurrences. The total area of the region under the influence of drought events from lowest to highest spanned from 233, 259.276 km 2 (in 2007) to 279, 189.364 km 2 (in 2002) and 2704.82 km 2 (in 2010) to 236, 082.70 km 2 (in 2008) for VHI and SPI, respectively. Results from this study revealed that the VHI gave a better representation of drought severity with continuous/consistent spatial values compared to the SPI.